The following is a quick hack that generates test data, processes it, and displays it in a grid form. The function table() is adapted from a post I made a day or two ago.

use strict;
use warnings;

my (%pairs, %animals, %owns, @names, @animals, @owns, @display, $name,
+ $animal, $x, $y);

@names = qw/Adrian Alannah Allison Angus Anna Ashton Aurelia Autumn/;
@animals = qw/cockatoo crane crow dove duck egret emu flamingo goose/;

for (1..($#names * $#animals / 2)) {
    $name = $names[int rand($#names + 1)];
    $animal = $animals[int rand($#animals + 1)];
    if (!$owns{$name}{$animal}) {
        $owns{$name}{$animal} = 1;
        push @owns, [$name, $animal];
    }   
}
@owns = sort { $a->[0] cmp $b->[0] || $a->[1] cmp $b->[1] } @owns;

print join "\n", map { "$_->[0] owns $_->[1]" } @owns;
print "\n\n";

for (values %owns) {
    @owns = keys %$_;
    $animals{$_} = 1 for @owns;
    for $x (0..($#owns-1)) {
        for $y (($x+1)..$#owns) {
            $pairs{"$owns[$x] $owns[$y]"}++;
            $pairs{"$owns[$y] $owns[$x]"}++;
        }
    }
}

@animals = sort keys %animals;
push @display, ['', @animals];
for $y (@animals) {
    push @display, [$y, map { $pairs{"$y $_"} ? $pairs{"$y $_"} : '' }
+ @animals];
}
table(' | ', \@display);

sub table {
    my ($separator, $arr) = @_;
    my ($i, @lengths, $length, $format);

    for (@$arr) {
        for $i (0..$#$_) {
            $lengths[$i] = length($_->[$i]) if !$lengths[$i] || $lengt
+hs[$i] < length($_->[$i]);
        }
    }
    $length = 0;
    $length += $_ for @lengths;
    $length += length($separator) * $#lengths + 4;

    $format = join $separator, map { '%-'.$_.'s' } @lengths;
    print '-' x $length, "\n";
    no warnings;
    print '| ', sprintf($format, @$_), ' |', "\n",
          '-' x $length, "\n" for @$arr;
}
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